[A Patient Developing Guillain-Barré Syndrome After Receiving the BNT162b2 COVID-19 mRNA Vaccine].

We report a 71-year-old woman who presented with paresthesia, progressive weakness, difficulty walking, diarrhea, and bladder dysfunction one week after she received the BNT162b2 COVID-19 vaccine. Her neurological signs and symptoms gradually worsened up to 27 days after onset, after which her weakness slowly improved without immunotherapy. Analysis of serial cerebrospinal fluid specimens showed gradually increasing protein levels. Results of a nerve conduction study suggested functional axonal disturbance. The clinical findings together with the monophasic clinical course were consistent with Guillain-Barré syndrome. Her previous history was negative for symptomatic infection. Serological and bacterial tests, including the presence of anti-glycolipid antibodies, were negative for prior infection. Few cases have been reported on the development of Guillain-Barré syndrome after the BNT162b2 vaccine. Our patient's syndrome was characterized by atypical proximal weakness of the dominant lower limb. (Received January 28, 2022; Accepted April 4, 2022; Published August 1, 2022).